3,500 New Yorkers Gather to Execute an 'Mp3 Experiment'

Divided into two groups according to shirt color (white or black), more than 3,500 strangers assembled at Nelson Rockefeller Park yesterday to carry out what's called an 'Mp3 Experiment.'

Despite being strangers, members of the crowd all shared one thing: They all visited the website of ImprovEverywhere, a performance art group, and downloaded an original MP3 file. The website instructed participants to show up on New York's Hudson shore at precisely 8:30pm and play the MP3 file, which includes instructions from a disembodied voice. The voice -- soft and encouraging -- told the strangers to perform activities like dancing, high-fiving and waving at one another. Finally, the Mp3 Experiment ended when the voice directed the now-friendly strangers to glow sticks and a dance floor at Nelson Rockefeller Park.

To what end do these anonymous gatherings work toward, you might ask? No one's sure, although social cohesion is a popular theory. They're incredibly fun, regardless, and they're becoming more and more common.